I can see how it could also apply, in a sense, to the level of danger you perceive. After all, that affects how you are armed, I assume. Cooper, I believe, described how some assume away danger when there was good reason not to do so. This doesn't apply just to situations in which you may be attacked by another person but by a dangerous animal. If I remember correctly, he mentioned being on a hunting trip in Africa. He along had his rifle with him while they sat around the campfire (or some such occasion) when something big with teeth and claws showed up. But it is human nature to be "extra careful" if you think there is a need to be.
I don't remember any older writers ever mentioning such a color coding system. That doesn't mean none existed, only that writers didn't mention it. However, not many writers of my father's generation and earlier ever wrote of self defense like Cooper. Do you suppose anyone else had any sort of awareness coding?
Shoot low, sheriff. They're riding Shetlands!
Underneath the starry flag, civilize 'em with a Krag,
and return us to our own beloved homes!
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